1. Field of the Invention
The present invention relates to a motor-driven brake having a multi-pad, and more particularly, to a motor-driven brake having a multi-pad for obtaining a desired large braking force from a motor operation force that is small relatively to the related art.
2. Description of Related Art
Motor-driven brakes are used as the next generation brakes for the combi-brake system and the brake by wire system (BBW) of vehicles, because they have a rapid response speed and can be precisely controlled, relatively to hydraulic brakes.
The combi-brake system, a system using hydraulic brakes for front wheels and motor-driven brakes for rear wheels, has the advantage that the structure is simple with improved braking force and response and the braking force is easy to control, relatively to the existing hydraulic systems.
The brake by wire system (BBW), a system using motor-driven brakes mounted on all of front wheels and rear wheels, has the advantage that it can reduce a braking distance and increase stability in braking because it can independently and precisely control braking forces for the wheels and easily control the braking forces relatively to hydraulic types.
However, motor-driven brakes of the relate art which are used in those systems have a limit that they need large motor torque being in proportion to a braking force to generate a large braking force, and accordingly, the output and size of motors should be increased. Therefore, there is a problem in that they are disadvantageous in terms of cost and package and disadvantageous in terms of weight too because the motors should be increased in size due to the increase in required braking force.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.